package com.kfm.servlet;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.Map;

@WebServlet("/logout")
public class LogoutServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        ServletContext application = req.getServletContext();
        Map<String, HttpSession> onlineUsers = (Map<String, HttpSession>) application.getAttribute("online");
        onlineUsers.remove(req.getSession().getId());

        // 销毁session
        req.getSession().invalidate();
        // 重定向到登录页面
        resp.sendRedirect("login");
    }
}
